Control valve



March' 3, 1,953

CONTROL. VALVE Filed June 8, 1949 R. AH. BRANDES ET AL 2 SHEETS--SHEET l March 3 1,953 R. H. BRANDE-s ET AL 2,630,136

CONTROL VALVE 4 Filed June 8, 1949 2 SHEETS-SHEET 2 55 #rra/amers Patented Mar. 3, I 1953 UNITED STATES PATENT OFFICE CONTROL VALVE Roy H. Brandes and Robert C. Treseder, Dayton, Ohio, assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application June s, 1949, serial No. 97,724

(o1. 1er- 623) 18 Claims. 1

The invention disclosed `herein relates to a double-acting reversely movable control valve that is adapted to direct the flow of iiuid pressure from a source port to and from either one of a pair of spaced control ports and is adapted to electromagnetic actuation for holding the valve open with respect to one port, or for reciprocatory movement to rapidly and alternately open and close the two control ports at a relatively high frequency, and thus due to the method of actuation, the valve is adapted to establish solid flow of fluid pressure thru one of the control ports with drain from the other control port, or intermittent flow of high frequency in the nature of short pulses first thru one port and then thru the other port. To accomplish these ends, the valve structure embraces an adjustable porting sleeve and a cooperative spool valve for controlling the ports, which spool valve has a floatingsupport on a plunger assembly that is provided with stops and preloaded springs that normally position the spool valve in a mid position bearing a denite relation with respect to the ports in the porting sleeve. Support means for the plunger assembly maintains concentricity of the plunger assembly with respect to the valve body. The plunger assembly carries armatures cooperable with eld magnets of the solenoid through a tapered air gap, which field magnets are also piloted or centered with respect to the support assembly. The support assembly for the plunger assembly is such that distribution of the movable valve parts and armatures tend to :counteract any bending or iiexing of the plunger :assembly normal to the spool valve, such that` when the control valve is mounted in a rotating structure with its plunger assembly generally at right angles to the action of centrifugal force, that there wiil be insuiiicient bending or flexing of the plunger assembly to effect any lateral movement of the spool valve relative to the porting sleeve. Secondary adjustments are provided for reducing the travel of the plunger assemblies when one of the solenoids is actuated and thus limiting the amount of either port opening. Provision is made for using the drain oil from each or the ports to lubricate the moving parts and also to cool the respective magnet assembly by which the plunger assembly'is actuated.

It is therefore an object of this invention to provide a control valve that is susceptible of relatively high frequency operation for alternate opening oi control ports, and which is adaptable for modulated operation to control the length of Aport opening such -that either ,pulse `like applica- 2 tions of iiuid pressure may be applied to both of the control ports, and differentially altered in operation to effect solid flow thru one of the control ports.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred embodiment of the present invention is clearly shown.`

In the drawings:

Fig. 1 is an enlarged view partly in longitudinal section and partly in elevation of the invention disclosed herein.

Fig. 2 is a detail of adjustment as indicated by line and arrows 2-2 of Fig. 1.

Fig. 3 is a detail in section of the electric terminal construction as indicated by line and arrows 3-3 of Fig. 1.

Fig. 4 is a schematic circuit diagram illustrating adaptations for the valve subject to the instant invention.

Fig. 5 is a transverse sectional view thru the valve substantially as indicated by the line and arrows 5-5 of Fig. 1.

Fig. 6 is an end elevation of the valve substantially as indicated by the arrow E of Fig. 1.

Fig. 7 is a sectional detail ci the plunger support substantially as indicated by the line and arrows 1-1 of Fig. l.

With particular reference to the drawings, I indicates a central block and support for the valve assembly, it having a central bore 2 under cut to provide annular grooves 3. 4 and 5 into which drill passages 6, 'I and 8 lead from the bottom surface of the block adapted to be connected by 'I with a source of fluid under pressure and to form control passages E and 8 leading to any double acting device to be actuated. Each of the bores 6, 'I and 8 ending with counterbores 5 adapted to receive a seal ring I0 compressble into sealing relation with an apertured plate II when the valve body is mounted thereon by hold-down screws not shown.

Fitting within the bore 2 of the central block there is a porting sleeve I2 providing ports I3 and l5 adapted to register with the annular grooves 3 and 5 of the central block, and an exterior annular groove I4 having a series of ports i6 connecting the groove I4 with the bore Il of the portingA sleeve. The annular groove I4 is always in communication with the annular groove 4 so that source pressure thru the passages T, 4, I5 and I6 may always be present at the central portion of the porting sleeve I2.

The porting sleeve l2 is adjustable longitudinally along the length of the bore 2 of the center block by means of an adjusting pin I8 contained within a bore I9 extending from the top surface thereof and opening by a reduced passage into the bore 2 of the center block. The adjusting pin I8 is provided at the inner end with an eccentrically located camming pin 2Q that projects into and closely fits the exterior annular groove ld of the porting sleeve I2. A screwdriver slot 2l on the outer end makes provision for turning the pin i8, and a iiange 22 seated in a counterbore 23 is engaged by a clamp plate 'il to hold the pin IS in the exact position to which it is adjusted. Hold down screws 25 passing thru the plate 2s and threaded into drillways 2e of the body l secure the pin it in its adjusted position. When the screws 25 are loosened the pin I8 may be turned and because of the eccentric pin 2li the porting sleeve l2 may be shifted a limited amount along the length of the bore 2 in the center block. A plurality of. seal rings 2l are disposed in grooves surrounding the porting sleeve l2 and are positioned on each side of the ports I3, Iii and I such as to prevent cross iiow and leakage of pressure fluid from one passage to another.

A valve spool 3u is slidable within the bore H of the porting sleeve and has lands 3i, 32 ap- -ropriately positioned at either end of the spool to coact in covering the control ports I3 and l5 when the valve is in the neutral or centered position. Between the lands 3| and 32 there is an annular groove 33 that is always open to source pressure available thru l, 4, I4 and I6. The valve spool Se is intentionally of small mass and has a relatively large internal bore thru which a plunger assembly 3s extends for control of reciprocating or longitudinal movement of the valve spool. The plunger assembly is made up or a rod threaded at each end to receive a nut 3S, the two nuts operating to maintain the plunger assembly in predetermined relation. Centrally disposed on the rod 35 there is a spacing sleeve 3l disposed between two retaining collars 3i? and 3e both of which are pinned in fixed relation upon the rod 35 by pins d, acting together to hold the spacing sleeve 3l against any longitudinal movement along the shaft 35.

The spacing sleeve 3l is considerably less in loutside diameter than is the inside diameter of the spool valve and thereby provides an annular space il between the member 30 and the spacing sleeve 3l such that the plunger assembly may be eccentrically associated, or even cocked with respect to the true axis of the valve element te. The adjacent end of the collars 33 and 3Q is larger in diameter than is the inside diameter er" the valve element 3G, and the length or? the spacing sleeve 3l is sumciently greater than the length of the valve element 3!) to make it possible for the valve element 30 to shift somewhat transversely of the plunger assembly, and yet be so eonnned between the collars 33 and that any movement of the plunger assembly will operate to shift the spool valve 3e within the bore of the porting sleeve I2.

Inasmuch as the opposite ends of the plunger assembly are identical in construction, a detailed description of one end of the plunger assembly and the solenoid means by which it is operated is believed to be suicient. Resting against the end the collar 39 there is a stop plate d5 that is slidable upon the rod 35 and is of suicient diameter to engage the end of the center block l surrounding the bore 2 as at 46 as a stop. The plate d5 has a plurality of holes 4'? permitting passage of uid therethru. A heavy spring 48 surrounding the rod S5 presses the plate 45 against the end of collar 3e and is enclosed in part by a socketed sleeve 49 and against which a laminated armature 5E! is forced by a spacing sleeve 5| under the clamping action of the hereinbefore mentioned nut 3%. Surrounding the socketed sleeve 49 and secured thereto by any convenient means there is a ilanged sleeve member 52 providing a plurality of lineally extending slots 53 within which are disposed antifriction balls 55 large enough to roll upon the outer surface of the sleeve 49 and to have a rolling' engagement within the bore of an axial sleeve 55 of a coned plate 56 somewhat as shown in Fig. 1. The sleeve 55 of the coned plate flares outwardly at 51 joining a dat portion 5S that seats against the end surface of the block l, and has an overhanging portion 59 that extends over the periphery of stop plate 45 to limit longitudinal movement of the plunger assembly. Fluid passages t are provided in the flaring portion such as to provide flow for hydraulic fiuid when the associated now portI be opened to drain. The coned plate is piloted on the end of the center block I by a peripheral flange El that engages in a rabbeted groove 62 of the block so that the sleeve 55 will be concentric with the plunger assembly 34. Screw devices 63, as shown in Fig. 5, secure the coned plate to the end of the center block. The relation and dimension of parts are such that the central block with the plunger assembly forms a compact valve unit in which the porting sleeve can be adjusted for centering or for proportional port opening in connection with a reciprocable plunger assembly. That assembly is rmly and accurately supported for positive and definite movement with respect to the porting sleeve which makes for valve operation to very close specifications and tolerances. The plunger assembly is longitudinally guided thru the agency of antifriction ball bearings supported mainly by the end plates that maintain the parte in predetermined relation thereby eliminating frequent adjustl'nentJ or faulty operation.

For moving the plunger assembly in either direction along the bore of the porting sleeve, a magnet assembly B5 is disposed as a cap over theperiphery of the cone plate 5S where it is held in place by screw devices E6 threaded into corners of the central block I. The magnet assembly 65 comprises a cup-like member 6l' within which is secured, by screw or like devices 'lc a field frame 'uhaving pole pieces 69 supportingxmargnet windings 'I0 connected by insulated leads 'All to terminal posts 12. The radially inner end of the pole pieces 69 are beveled in a way to provide a conical air gap 13 cooperating with the conical armature 50. The open end of the cap 61 is taper bored to receive a wedge ring l concentric therewith and which is secured thereto by a rubber-like sleevev'i bonded or vulcanized to both vthe wedge ring 'M and the rim oi the cup.

Figs. 'l and 3 show one modication of a terminal structure for the field coil, in which the tertninal post 'I2 is secured in an insulator 16 by means' of a head 18 seating' against a compressible seal 19. The block 16 is secured upon the upper face of the cap 61 by means of screw devices which forces the terminal member i2 against an eyelet 8l supported by an insulator 82 recessed in a socket 83 of the cap 61. The lead wire I is cnncted to the eyelet Bi and passes thru insulators 84 and 85 to the field winding 'I0 providing current connection between the Winding 10 and a connector that may be frictionally engaged with the terminal l2. A second and similar terminal leading to the other end of the coil 'I9 may be grounded upon the frame in any convenient manner. In Fig. 5 a modication of the terminal structure is shown in which terminals 12a and 12b supported by the insulated bloclf: 'I6 are surrounded by nonoonducting sleeved washers 86, and which encloses the leads 1I. Here the terminal 12a is adapted for threaded engagement with a connector while the terminal 72b receives a nut 81 engaging a connector 88 secured beneath the head of one of the screw devices 83 and thereby forms a ground connection for the coil l0, since the screw device 80 threads into the rim of the cap 61.

Each magnet assembly is a complete subassembly and is adapted to be fitted over the end of the plunger assembly to engage the valve assembly about the end plate 58 as shown in Fig. 1. The resilient bond .l5 between the wedge ring and magnet cap is very thin and of insulating properties so that adjustment of the magnetic air-gap I3 can be accomplished by the aid of electrical measuring instruments. The valve support assembly and the plunger assembly are concentrically arranged due to the piloting of the plate 56 upon the block I, and the preloaded ball bearings 52 to 55. The magnet assembly is concentrically arranged about the end of the plunger assembly due to the piloting of the rim of the cap over the edge of the plate 58. It is desirable that the air gap 'I3 be at a minimum yet large enough that there will be no contact between the armature 59 and i-leld poles 69 when the plunger assembly moves against the stops in either direction. An electrical measuring instrument of the proper type connected across the central body I and the cap 6'! will show a current value when the magnet parts are in contact. In assembling the magnetic unit upon the valve assembly, the plunger assembly is forced in one direction suiciently that the stop plate 45 engages the associated stop abutment 59. While the parts are held in that position the magnet assembly is passed over the plunger' assembly and with the wedge ring 'I4 piloting around the flange Si of the end plate 59. Shims 89 are disposed in suiiicient quantity between the block I and the edge of cap 61 such that the armature 59 in the depressed position will not engage the pole piece B9 at any point which is indicated by the absence of any reading on the electrical measuring instrument. seating has been accomplished the screw devices 66 are tightened to hold in place. Releasing the depressing force allows the plunger assembly to return to its centered relation, and forcing in the opposite direction followed by similar procedure in mounting the other magnet assembly makes the control valve ready for use when it is mounted upon the support I I and connected inte the electric circuit.

Energization of either magnet coil 19 will then operate to shift the plunger assembly longitudinally of the bore of the porting sleeve. the plunger assembly riding on the ball bearings 54 to the extent defined by the spacing between the edge of the stop plate 45 and the stop abutment 59. In some instances it is desired that the longitudinal movement of the plunger assembly, in other words the amount of port opening of the valve. be less than` the amount provided by the stop plate 45 and abutment 59. An auxiliary ad- When that justment is supported by means of a nut 90 mounted in the center of the cap 61 by rivets or the like 9i and which provides a screw or like device 92 whose tip 93 may be moved toward or away from the end 94 of the plunger rod 35 b-y threading the screw 92 into and out of a nut 99. Thus by threading the screw inward the gap between the stop elements is diminished. With reference to Fig. '1, the spacing of auxiliary stop 93-94 is much less than is the built-.in stop 45-59. Yet the spacing is such that upon energization of the right hand magnet coil. 'I0 the plunger assembly 34 will be moved to the right, iiuid pressure owing from the source port 'l to enter the groove 33 between the lands of the sleeve valve and pass out the control port I5. The adjustment of auxiliary stop on the other end of the plunger assembly may be more or less than the aforesaid right-hand auxiliary stop, in which instance movement of the plunger in the other direction would be likewise more or less, effecting a correspondingly different port opening for I3 than for port I5.

Whenever the plunger assembly is moved in either direction suicient to open one of the control ports I3 or I5 then the other control port I5 or port I3 is opened to drain which flows from the end of the porting sleeve I2 thru the holes 41 in the stop plate and thence thru the holes 60 in the cone plate and thru the ball bearing support for the assembly to the interior of the magnet assembly where the hydraulic fluid surrounds the irregularities of the eld frame 68, the field winding 10, as well as iiows thru the air gap 'I3 to exit thru 95 to the exterior of the casing. The exhausted hydraulic fluid thereby owing through the magnet assembly acts to lubricate the bearing for the plunger assembly, and to cool the windings and other parts of the magnet assembly.

One adaptation of the use of the valve herein disclosed is for control of a rotatable apparatus in which the valve is mounted within a rotating reservoir in such manner that the plunger rod 35 is at right angles to the action of centrifugal force. The speed of rotation is such that centrifugal force tends to bow or bend the plunger rod 35 between the spaced support points which would normally effect binding of a valve element carried thereby in sliding thru a porting sleeve. The tendency toward binding and bending of the valve parts has been substantially eliminated by distributing the mass of the assembly along the length of the rod 35, and by placing the supporting bearings in such position and relation that any tendency of the middle portion of the rod to bend or bow outwardly is counteracted by the mass of the armature 59 on the opposite side oi the support bearing, which results in reducing the eccentricity of the rod 35 and sleeve 31 with respect to the valve element 30. The spool valve 30 being of small mass is less effected by the cen trifugal force, and due to its floating relation as supported by the plunger assembly, is more easily moved when current is applied to either magnet assembly.

The control valve is susceptible of different types of operation as will be apparent in the consideration of the schematic showing of Fig. 4. The valve assembly may be moved to one port opening and held there as long as desired by a continuous application of current to the respective field winding, or the valve may be reciprocated ata relatively high frequency by alternate application of current pulses to the oppositely disposed winding 10. Assuming that the stops for the plunger assembly are equally spaced from the valve in its centered position then equal altornate electrical pulses applied to the magnet winding 16 will effect equal alternate opening of the valve ports. Each time the magnet windings '5G are energized they act upon the plunger assembly to move the assembly against the respective stop and hold it there until the cessation of current in a respective winding. Specically, and referring to Fig. l, energization of the right hand coil l0 pulls the plunger assembly 34 to the right until the stop disc l5 engages the stop abutment 59. Continuation of the current in winding "IG holds the plunger assembly in that position until the current is interrupted. Movement of the plunger assembly toward the right compresses the left hand spring 43 between the socket member 43 and the respective stop plate 35. There will be no change in the fleXure or the right hand spring 48. Upon current interruption the compressed left hand spring le rew turns the valve assembly to the centered pcsition or that position in which both stop plates i5 engage the end of the center block l at their peripheries which is indicated at d3. Energizam tion oi the other or left hand coil ill moves the plunger assembly toward the left in the same manner. If the two magnet windings ld are alternately energized then the plunger assembly is reciprocated within the bearings iid at the irequency of alternate energization of the winding lli, the interium of coil energization allowing or a spool valve 36 and a supporting plunger assembly to return to the centered position. The plunger assembly will always return to the centered position even tho the centering springs di? are compressed to different degrees which might occur by running one of the nuts 3d on to the rod 35 further than the other one.

In the illustration of Fig. 4 the Valve is schematically shown as having the porting sleeve l2 surrounding the plunger assembly 34 and having its ports I3, I4 and I5 connected by passages HES, |04 and |55. Passages |03 and Hi lead from ports i4 and I5 to chambers Hit and le? cic a fluid pressure servo |08 containing a double acting piston |09 itted with a rod l Iii for shifting a variable load device driven by an engine shaft i l2 in the direction of arrow A. The passage Illd is a pressure supply passage leading from a fluid pressure pump I3 having an intake H4. The source pressure |64 is protected by a pressure control valve I i5 that maintains a pressure potential within the line Idd sucient to ctuate the piston |09 of the servomotor when the valve connects the source port Id to either of the control ports |3 or E5.

n the illustration of Fig. 4 the magnet windings are designed lllL for the left hand and 'MER for the right hand winding and they are joined by a common conductor ||3 leading to one pole of a source of current such as a battery l ll, the opposite pole of the battery connecting by wire I i3 with a brush I i3 riding upon a contact drum lili. The drum l2@ is covered with two contact elements |2i and |22` each of which have triangular extensions |23 and |24 respectively dovetailing with each other lbut insulated by a nonconducting separation strip 25. Brushes |23 and l2? rub against contacts |21 and |22 respectively and are connected by leads 28 and I 29 with the opposite ends of magnet windings idR and WL. Branches |33 and |3| connect leads 28 and IZS'With switch terminals |32 and |33 adapted to be engaged by a blade |34 connected by |35 joining the wire liil from theA battery A constant speed source |36 powered by an electric source |31 drives a shaft |33 which rotates the contact drum |23 which is mounted upon the shaft |39 longitudinally shiftable by means of a manual lever |30. The constant speed source |35 is controlled by an adjustable knob 5| which selects its speed at which the drum |20 will be driven.

Due to the organization of parts set out in Fig. 4 the load devi-ce |I| may be held at fixed position or it may be adjusted to either increasing load or decreasing load by means of pressure applied to the proper side of the piston |89 of the servo unitl |08. For maintaining the position of load device ||I, assuming that it requires the same amount of power to shift the device in one direction as the other, the brush H9 will ride up-on the middle of the drum |20 such as to rub on equal peripheral portions of the contact lobes |23 and |24. With a drum rotating at constant speed then the electrical energization of either of the windings '131i or 'FR will be equal, and the port opening of control ports I3 and I5 will be equal. Because of rotation of the drum I2@ the winding 'iL and winding 'Ulli'J will be alternately energized and the valve assembly will be reciprocated for equal periods 0f time in opposite direction. Also the period of port opening at I3 and i5 will be equal in duration of time which will allow equal pulses of i'iuid pressure to 'be applied to opposite sides of the piston |33. Under those conditions there will be no resultant movement of the piston and the load device III will be maintained in a set or selected position. If the manual lever lll@ is oscillated such as to shift the drum i 2li along the shaft i33 then the engagement of the brush EIS upon the successive contact elements |23 and 124 will be unequal. The dwell upon one contact element will be shortened while the dwell upon the adjacent contact element will be lengthened which results in one of the magnet windings 'FSL or 'llR being energized for a longer time than the other. In consequence of this the plunger assembly will be held in one extreme position for a longer period of time than it will be held in the opposite extreme position, and as a consequen-ce, the fluid pulse delivered to one side of the piston will be correspondingly longer in time than is the pulse delivered to the opposite side. There is then a resultant movement of the pis ton 09 which rotates the load device in a corresponding direction. The manual lever MU may be shifted so far as to move the contact drum |23 far enough that the brush ll rides upon the connecting portion of the contacts 23 or |24 which then effects a continuous ow of cur rent to one or the other of the magnet windings 'IOL or 'IGR so long as the drum and brush re main in that relation. With a continuous flow of current to either of the windings l'ilL or the Valve assembly will be moved against one of the stops and held there tho the drum continues to rotate thru a number of normal contact engagements. With the valve assembly held in one extreme position there is accomplished solid iiow of fluid pressure from the source port la to either of the control ports I3 or I5 until the piston |09 moves to its limit of travel. VOn the other hand the switch blade i3d may be manually moved to engagement with either of the terminals |32 or |33 and thereby effect conaesdia 9 tinued energization of one of the magnet coils 'IGR or 'IBL which establishes solid ow to one side of the servomotor |08 in a corresponding manner.

In Fig. 4 the variable load device III is disclosed as being a propeller blade so mounted upon the rotatable shaft I I 2 that its trailing edge portion i@ provides a much larger area than its leading edge portion ISI and is of such character that tho rotating with the shaft II2 there is a tendency for the blade to shift in a clockwise direction which would be towards the low pitch position. In a construction so characterized it would be necessary to maintain a greater shifting force in the chamber IU'I at all times of propeller rotation. That would mean that in order to maintain a xed position of a load device III larger pulses of fluid pressure would have to be applied to the chamber IUI than to the chamber IDB in order to hold the piston against movement. The characteristics of the valve disclosed in Figs. 1 to 6 is such that that result may be obtained. The adjustment of the stops are such that the connection of ports I5 with supply port I4 can be maintained for a longer period of time, or for a greater extent of opening than is the time or opening of control port I3 and vice versa. The maximum port opening that can be accomplished is determined by the spacing of the stop plate 45 and the abutment 59. Thus if it is desired that the port I5 be opened wider than the port I3 the auxiliary stop on the left hand end of the valve assembly is run in such as to reduce the maximum stop to a value that Will permit the flow thru control port I3 plus the tendency of blade shift toward the low angle position to adjust the balance of the force applied thru control port I5.

While the embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. A control valve adapted to control the reverse movement of a load device actuated by fluid pressure, the combination comprising, a body having a central bore and a porting sleeve therein, a spool valve reversely shiftable along the porting sleeve, means for reversely moving the spool valve to opposite sides of a mid position, opposing spring means for returning the valve to the mid position, means exterior to said body for adjusting the porting sleeve along the bore of the body so that ports in the porting sleeve will be closed when the spool valve is in the mid position, and stops limiting the opening of the valve.

2. A control valve adapted to control the reverse movement of a load device actuated by fluid pressure, the combination comprising, a body having a central bore and a porting sleeve therein, fluid pressure source and control ports and passages provided by the body and sleeve, a hollow spool Valve slidable within the porting sleeve and adapted in a mid position to close the control ports, a plunger assembly extending axially through the spool valve for shifting it to positions on opposite sides of the mid position, spring means normally centering the plunger assembly at the mid position, antifriction bearings supporting the plunger assembly for reciprocating motion, and stops limiting the amount of reciprocating motion.

3. In a reversely operating valve having a cylindrical sleeve ported to provide a pressure supply port and a pair of control ports, the combination comprising, a spool valve cooperable with the sleeve and having spaced lands for coincidentally closing the control ports of said sleeve, a plunger assembly extending axially through the spool valve for shifting it to uncover the ports of said sleeve, and means including a second sleeve concentric to said plunger assembly and of greater length than said spool valve providing for relative lateral movement of the plunger assembly relative to the spool valve without causing the spool valve to chafe the porting sleeve.

4. In a reversely operating valve having a cylindrical sleeve ported to provide a pressure supply port and a pair of control ports, the combination comprising, a spool valve having a pair of spaced lands adapted to cover the control ports of said sleeve, a plunger assembly for controlling the movement of the spool valve along the sleeve, mechanical stops for limiting the maximum opening of said control ports, and auxiliary stop means engageable with the plunger assembly for adjusting the limit of the maximum port opening.

5. In a reversely operating valve having a cylindrical sleeve with a bore ported to provide a pressure supply port and -a pair of control ports, the combination comprising, a spool valve with a bore and having spaced lands movable along the bore of the sleeve to control fluid flow through the control ports, said spaced lands having a width which is at least equal to said control ports, means for reversely moving the spool valve, including a plunger assembly extending through the bore of the spool valve and having fixed collars at opposite ends of the spool valve, stop discs and means yieldably urging the discs against the collars, spaced stop means disposed on opposite sides of the stop discs to limit the plunger movement and dene the maximum port opening, and anti-friction means supporting and piloting the plunger assembly with respect to said porting sleeve.

6. A reversely operable solenoid actuated valve for controlling fluid flow through a pair of control ports, the combination comprising, a support body having a cylinder bore therethrough, a porting sleeve disposed in the bore and having ports adapted to connect a pressure source with control passages provided by the support body, means carried by the said body for centering the porting sleeve along the said bore, a plunger assembly adapted to move along the bore of the porting sleeve and having a landed valve element adapted to control iiuid now through the control ports, stop discs on the plunger assembly adapted to engage the support body around the periphery of sai-d cylindrical bore, a plunger support assembly at each end of the support body for piloting the plunger assembly and including a plate with a sleeved extension, a collar carried by the plunger assembly concentric with the sleeved extension, antifriction balls disposed as a reciprocating bearing between the plunger collar and the sleeved extension, compressible spring means on the plunger` assembly disposed between the collar and the stop disc normally pressing each stop disc against the support body around the bore or the support body, said plate of the plunger support assembly having a spaced abutment overhanging the periphery of the stop plate to limit movement of the plunger assembly in one direction with respect to the porting sleeve.

` 7. A reversely operable valve for controlling fluid ilow through either of a pair of spaced control ports, the combination comprising, a support body having a through bore and passages for supply and distribution of iiuid pressure opening from s aid bore, a cylindrical valve element operable in said bore to control the flow through said passages, means centering and sup porting said valve element with respect to said bodythrough bore and adapted to shift the valve element ineither direction, a magnet assembly secured to each end of the support body for actuating the valve element, and means disposed between the support body and the magnet assembly for adjusting the air-gap of said magnet assembly. Y

8J. In a spool and sleeve type valve adapted for mounting and operation in a rotary structure where a valve actuating plunger is disposed at right angles to the centrifugal field of rotation, the 'combination comprising, a porting sleeve having ports adapted to be connected for fluid flow, a valv'ing sleeve slidable along the bore of the porting sleeve for controlling the iiuid iiow, said valving sleeve having a large diameter bore, an actuating rod extending through the bore of said valvhg sleeve, Va spacing sleeve on the rod having a length mihutely greater than i@he length of the valving sleeve and an outsidev diameter sufciently less than the bore of the valving sleeve to provide ier lateral, relative shift,l a pair 0i collars secured to the rod and abutting the ends o f the spacing sleeve and for engaging the end of the valving sleeve, means for moving the rod toactuate the valving sleeve while the valve and supert are rotating, and bearing means for each end of the red for guiding the redV movement whereby any deflection of the rod dueto action` o centrifugal force isinot transmitted to the valving sleeve.

9. A double acting valve adaptedto be mounted eh` e rotating device for. Cent-rolling the ew 0f ilud pressure to a plurality ofV control ports while the `device and valve are rotating, the combination comprising, a central block providingl fluid passages,` teA be controlled, and having a bore adapted te enclose. a eehtrel Valve mechanism, a movable valve member adapted to control said iiuid. passages. a. red. assembly for moving seid. valve element, armatures mounted on opposite ends of saidrrod assembly. means fer Diletirie the rod assembly in concentric relation to the 5.016, 0f said central block, magnet means for actuating thearmature in either direction,stops providedrby the rod assembly and central block preventing` engagement of the armature and magnet means, and means independent of said stops for adjusting theY air, gap to an amount greater than thev minimum provided by the saidv stops.

10Thel combination set forth inV claim Si,v wherein the magnet means has va iield i'rameiwithA poles that pilotsA over the rod assembly forthe. valve and provides a conical air gap between the armature and field poles, and shims disposed between` the central blockand the magnet as sembly'tqiprevent the engagement ofiarmature and fleldfframe. i

1 1, In anv electromagnetic control valve,Y the combination comprising, a, valvebody providing a cylindrical bore and having pressure supply and control ports opening therefrom, a valve spool movablewalilig the bore to control 4fluid iiew end .drain through the ports ef seidbedy, actuating' means for the valve spool including an) armaturepole piece land magnet coil, bear? ing means supportingthe armature and m-ain- 112119195.- @Ofl .iiiiy -Wiiiiihebereei Seid body! l2 and means whereby movement of the valve spool to a port drain position exhausts the draining iluid through the bearing and magnet coil to cool the same.

12. ln a solenoid actuated control valve adapted to eiect the application and drain of fluid under pressure to and from either of two ports, the combination, comprising, a body providing supply and control ports to be controlled, a pilot valve assembly having a valve spool for controlling the fluid flow to either of the control ports, a laminated armature secured to opposite ends of the pilot valve assembly for reversely shifting the pilot valve to an extreme position on either side of mid position, preloaded spring means biasing the pilot valve assembly to the mid position, a magnet assembly including pole pieces and field coils surrounding opposite ends of the pilot valve assembly for energizing the armatures when movement of the pilot valve is desired, and means including the exhaust of fluid medium drained from either of the control ports for cooling the said eld coils.

13. The combination set forth in claim l2, wherein antifriction ball bearing means support the pilot valve assembly for lineal movement, and stops are provided limiting the maximum amount of lineal shift of the pilot valve assembly.

14. In a double '-acting'solenoid actuated control Valve, a sleeve providing fluid pressure supply and control ports,l a cooperable valve member adapted to stop all ilow through the sleeve or direct flow through one or the other of the control ports, an actuator assembly for moving the valve member in either direction, said actuator assembly being provided with stop discs and preioaded springs, for centering the valve member in port closing position, ball bearing means supporting the actuator assembly substantially concentric with said sleeve, and electromagnet means for actuating the actuator assembly, said stop discs and bearing means providing openings for the drain of lexhausted iiuid pressure through the bearing means'and electromagnet means for lubrication and cooling ofthe same.

15. In a control valvev adapted to control the reverse movement oi a load device actuated by fluid pressure, thecombination including, a body having a centrali bore and a, cylindrical` porting sleeve: therein, saidY sleeveV having openings to provide for-a pressure supply port and controlports, a spool valve reversely shiftable along thesupporting sleeveand` having spaced: lands of greater width than said control ports, means forreversely. moving` the spool valve to opposite sides of amid position, opposing spring means for returning said. valve to themid position, and;V

means, exterior oi"` said body. for adjustingthe porting sleeveA along thebore of the bodyf for differentially varying the respective'openingsv of. said control ports.-

i 16. in a reversely.operatingvalve hai/ug a cylindrical sleeve ported to: provide a pressureA supply port; and a pair ofcontrol ports, the com bination including, aspool'valve having a-.rpair ofspacedalandsoij greater Widththan. saidcon? trol ports. a plunger assembly for con Vtolling. they movementof. saidvalve along said e' means normally detre rmining,v the opening of saidpontrol portsand ausm iusteble means eiieeseeble withfsaidfpl sehiblif.. ier; varying. the. ieepeetive said controlports. i*

l'i'. A reversely operable,valvefor` controiling fluid flow vthrmigln either of apen' ci. spaced conf trol ports including, a support body having a through bore and passages for supply and distribution of fluid pressure from said bore, a cylindrical valve element operable in said bore to control the flow through said passages, means centering and supporting said valve element with respect to said body through bore and adapted to move the valve element in opposite directions, a magnet assembly secured to each end of the support body for actuating said means, independently adjustable members disposed at opposite ends of said means for varying the amount of movement of said valve element in opposite directions, and means disposed between the support body and magnet assembly for adjusting the air gap of said magnet assembly.

18. A control valve adapted to control the reverse movement of a load device actuated by uid pressure including, a support body having a through bore and a cylindrical sleeve, fluid port body for actuating the valve element, 30

means for adjusting the cylindrical sleeve along the bore of the body, means for Varying the amount of movement of said valve element in opposite directions, and means for adjusting the air gaps of said magnet assemblies so that different openings of said control ports are effected upon movement of said valve element in opposite directions.

ROY H. BRANDES..

ROBERT C. TRESEDER.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 825,588 Demarest July 10, 1906 972,430 Beggs Oct. 11, 1910 1,028,657 Aubert June 4, 1912 1,166,210 Holley Dec. 28, 1915 2,145,977 Foster Feb, 7, 1939 2,194,782 Baade Mar. 26, 1940 2,307,585 Harrington Jan. 5, 1943 2,396,643 Ganahl Mar. 19, 1946 2,404,349 Brant July 23, 1946 2,407,184 Sparrow Sept. 3, 1946 2,410,404 Buchanan Nov. 5, 1946 2,412,549 Yates Dec. 10, 1946 FOREIGN PATENTS Number Country Date 503,347 Great Britain Apr. 5, 1939 

